Emerson’s Marcio Donnangelo and Marcelo Dultra presented Reducing Data Complexity on Affirmative Defense Claims with PRV Monitoring System at the 2022 4C HSE Conference. Here is their presentation abstract:
Despite the efforts to stay compliance, operation isn’t totally free from unauthorized events to happen. If that happens, Affirmative Defense should be considered. However, not knowing the frequency of emissions events, the causes of the event, the quantity and its impact, the emission duration, the need for startup, shutdown, and maintenance activities, etc. could be unclear in the process of evaluating the Affirmative Defense claim. Monitoring PRVs to immediately identify bad actors is critical to cover the gaps in these questions. Taking the action to replace PRV in minutes without disrupting the process is also possible with PRV selectors. Join this section to learn how.
Marcio opened by defining affirmative defense of emissions by proving steps such as using good practices to minimize emissions, taking prompt action, minimizing bypass of pollution control equipment, documenting incidents, and having minimal incidents.
Marcelo noted that a pressure relief valve (PRV) is not the source of the problem but a symptom of the overpressure event. They are the last line of defense to diffuse an overpressure event. A better understanding of relief events will enable better regulatory compliance.
PRVs are simple mechanical devices that will vent pressure when the inlet pressure overcomes the spring holding the valve closed. There is no feedback in a traditional PRV when it opens to release pressure. Marcelo noted that they are difficult to service since they are typically located in difficult locations—tops of tanks and other limited accessibility locations.
Marcio & Marcelo noted that an analysis of service records showed that 20% of the PRVs leak below 50% set pressure, 8% leak so excessively that they do not open, and there is no record of when and why the valve started to leak. Overpressure events can cause issues with emissions, production, reliability, and safety.
The Rosemount 708 Wireless Acoustic Transmitter is a non-intrusive sensor that clamps directly onto the PRV vent pipe surface. When coupled with a Rosemount 2051 or 3051 Wireless Differential Pressure Transmitter to detect the lift, time, and duration of a release event.
An Anderson Greenwood Safety Selector Valve (SSV) provides a dual relief system to enable switching between the primary relief line to the backup relief line to help with affirmative defense by taking prompt action and allowing the PRV to be repaired without shutting down the process.
Plantweb Insight for PRVs provides analytic tools that create actionable insights for informed decisions and prioritization. This application has pre-built analytics, which allows simple interpretation, including alerts to abnormal situations and conditions.
Visit the Pressure Relief Valve Wireless Monitoring section on Emerson.com for more on how you can bolster your affirmative defense in emission incidents.